Mitigation of server's load by queries for non-existing domains

[Tony Finch]

Tomas Hozza <thozza at redhat.com> wrote:
>
> Recently I was trying to find a mechanism in BIND that could prevent the
> server from processing a recursive query for non-existing domains.

Have a look at https://www.isc.org/blogs/tldr-resolver-ddos-mitigation/

> I was thinking about using RPZ with QNAME policy trigger, but this
> applies only to the responses to queries and still makes the server to
> try to resolve it.

RPZ has a "qname-wait-recurse no" option.

Tony.
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